Conversations with the Air Force

The purpose of the MFL staff meeting on 26 September 1958 was to determine the support requirements needed from the Air Force. A number of topics were discussed including safety zones, construction costs, fuel requirements, instrumentation, a service structure, and a launch site. The matter of a site, for what would eventually be launch complex 34, received further attention that Friday afternoon when Debus introduced the Saturn project to Maj. Gen. Donald N. Yates, Air Force Missile Test Center Commander. Debus suggested placing the new complex in the central part of the Cape near pad 26. That pad was presently in use for the Jupiter program, but would be phased out in 1960. Yates believed that construction near LC-26 would interfere with other contractors and pose safety problems. He suggested the use of areas near complex 20 (Titan), complex 11 (Atlas), or at the north end of the launch area, which had been tentatively reserved for large boosters. 3

During the next two weeks an MFL facilities team made a preliminary survey of five possible sites. James Deese drew upon eight years of Cape experience in directing the survey. The team focused much of its attention on ground safety. The potential blast effect of an explosion on the pad established a ground safety zone and a minimum intraline distance. The safety zone, marking the danger area for exposed personnel, would be cleared of all persons 39 minutes prior to launch. The minimum intraline distance delimited the area within which a pad explosion would cause damage to adjacent pad structures or vehicles. Deese estimated that the fuel would have half the explosive force of TNT. With an estimated fuel load of 476 tons (equivalent to 238 tons of TNT), the three-stage Saturn would require a ground safety radius of 1,650 meters and intraline distance of 400 meters. The proposed firing azimuths (44 to 110 degrees) excluded sites that would result in overflying permanent launch facilities already constructed to the east.4

The Deese team recommended only one site, an area approximately 300 meters north of complex 20. By using the existing Titan 1 blockhouse (launch control center) at LC-20, costs and construction time would be minimized. The Air Force Missile Test Center objected to this location, contending that the Saturn pad should be at least 610 meters from other structures. This precluded joint use of the Titan blockhouse, because the data transmission equipment used in checkout of the Saturn would be adversely affected by voltage drops over a 610-meter circuit.* MFL arguments that the Air Force recommendation would increase facility costs by 30% and construction time by four months proved to no avail. In mid-January, after a six-week delay, the Advanced Research Projects Agency sited the Saturn complex 710 meters north of pad 20.5

* Some MFL officials believed the Air Force simply did not want to share blockhouse 20. The Air Force, however, consistently gave range safety a high priority. As General Yates recalled, the Air Force received numerous complaints from contractors because of concessions the Missile Test Center made to

MFL.

3. Debus to C.O., Atlantic Missile Range (hereafter cited as AMR), "Juno V Program," 1 Oct. 1958; Robert F. Heiser, Technical Asst., Off. of the Dir., MFL, memo for record, "Juno V," 26 Sept. 1958.

4. Deese to Debus, priority TWX, "Feasibility Study and/or Criteria for a Launch Site at AMR for a Clustered First Stage of Juno V Project," 8 Oct. 1958; Koelle, ed., Handbook of Astronautical Engineering, pp. 28-1 to 28-10; MFL, Juno V(Saturn) Heavy Missile Launch Facility, 1st Phase Request, 2nd Phase Estimate, by R. P. Dodd and J. H. Deese, 14 Feb. 1959, pp. 2-3.

5. Deese to Debus, "Feasibility Study for a Launch Site"; Warren G. Hunter, ARP A Coordinator, SSEL, memo, "Meeting at MFL, CCMTA on Juno V Launch Complex," 10 Nov. 1958; Pan American Aviation, "Juno V Program Siting Study," 24 Oct. 1958, pp.1-3.

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Writing the Criteria Book

Criteria development for the Saturn complex proceeded more cordially. Close coordination was required between four groups: MFL, the Systems Support Equipment Laboratory of the Development Operations Division at Huntsville, the Jacksonville District Office of the Army Corps of Engineers, and an architect -engineering firm. Their goal was to collect and organize all the data necessary for satisfactory design and construction. The procedures used in developing Saturn launch criteria followed a pattern set in earlier programs. MFL and the Systems Support Equipment Laboratory prepared basic data on all launch facilities and equipment. The architect-engineer then formalized the data in a criteria book. The Army Corps of Engineers reviewed this document for cost, utility, and compliance with federal and Atlantic Missile Range codes. The launch criteria book provided a general description of facilities, proposed methods of construction, the placement of utilities and equipment, facility dimensions, distances between facilities, cost estimates, and preliminary drawings.6

Launch Complex
The master plan for launch complex 34.

The blockhouse for LC-34 was patterned after the control center at complex 20. The reinforced concrete design permitted the planners to locate the structure 320 meters from the launch pedestal. A domed roof would be built up in three layers: an inner layer of reinforced concrete 1.5 meters thick; a middle layer of earth fill 2.1 to 4.2 meters in depth; and a 10-centimeter cover of shotcrete. The last, a concrete with a high cement content was pressure driven through a 15-centimeter tube onto a reinforced mesh screen. The 930 square meters of floor space provided room for 130 persons, with test and launch consoles, instrumentation racks, remote control fueling devices, and television and periscope equipment for the observation of activities on the launch pad. Blockhouse operations required substantial air conditioning for such equipment as computers, as well as for the people. Should a delay in firing occur after the rocket was fueled, the blockhouse could be buttoned up for 20 hours. Two tunnels provided escape routes in case an explosion sealed the door.7

Two Cape veterans, R. P. Dodd and Deese, drew up preliminary criteria for the launch complex. Their plans called for a two-pad complex with only the northern pad (pad A) constructed initially. A raised concrete circle 130 meters in diameter would form the base of the pad. The central area's slight depression facilitated replacement of refractory brick after a launch. Dodd included a water deluge system to reduce the intense heat and wash away spilled fuel, which would be channeled toward a perimeter trench. A skimming basin would prevent kerosene from entering the area's drainage ditches. Beneath the pad, a series of rooms provided space for mechanical and electrical checkout and firing equipment such as terminal boards, instrumentation racks, electrical cables, and generators.

Three facilities along the south edge of the complex would service the Saturn's propellant needs. In the southeast corner near the ocean stood tanks for RP-1, a grade of kerosene, to fuel the Saturn I booster (first stage). The liquid oxygen (LOX) tank in the middle of the southern boundary stored the oxidizer for all Saturn stages. This tank was insulated; in its liquid state, oxygen is cryogenic - super cold - with a boiling temperature of 90 kelvins (-183 degrees C). Dodd and Deese placed a high-pressure-gas facility in the southwest corner of the complex, near the blockhouse. The tanks in this storage area held two gases, nitrogen and helium, used in launch operations. Large amounts of nitrogen were used to purge and dehumidify the cryogenic lines that ran from the LOX tanks to the Saturn vehicle. The nitrogen also actuated LC-34's pneumatic ground support equipment. On later launches, gaseous helium would be used to purge the hydrogen fuel lines to the Saturn upper stages. With an even lower temperature than liquid oxygen, liquid hydrogen boils at 20 kelvins (-253 degrees C). Since nitrogen would solidify in the presence of liquid hydrogen, helium was substituted. A few bottles of nitrogen and helium went aboard the launch vehicle to pressurize some of the subsystems.

In the final plans, the flame deflector and its spare were parked north of the pedestal. The service structure pulled away on rails running from the pad to a parking area 185 meters west. The designers placed the umbilical tower on the northeast side of the launch pedestal. Eventually 70 meters high, it would carry fuel lines and other connections to the Saturn before liftoff. Two requirements governed the location of the umbilical tower and the service structure: the need for clear lines of sight from the erected launch vehicle to radar and telemetry stations in the industrial area 3 kilometers to the southwest, and an anticipated launch azimuth of 75 to 90 degrees.8

6. Glen W. Stover, Chief, Facilities Br., AMR, Army Field Off., memo for record, Criteria Contract, Juno V Facilities, 10 Nov. 1958; Maurice H. Connell and Assoc., Heavy Missile Launch Facility Criteria (Miami, FL, 15 Mar. 1959).

7. ABMA, Juno VDevelopment, p. 55; LOD, "Complex 34 Safety Plan for SA-1 Launch," 24 Oct. 1961, p. 2; Porcher interview.

8. MFL, Juno V (Saturn) Facility, Connell and Assoc., Launch Facility Criteria; Sparkman interview, 13 June 1974. For detailed descriptions of the Saturn C-1 Launch Complex with its ground support equipment, see Marshall Space Flight Center (hereafter cited as MSFC), Saturn SA-1 Vehicle Data Book, report MTP-M-S&M-E-61-3 (Huntsville. AL. 26 June 1961), pp. 133-65, and MSFC, Project Saturn C-1, C-2 Comparison. report M-MS-G-113-60 (Huntsville, AL, 16 Nov. 1960), pp. 33-47, 123-290.

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Problems in Design

At Huntsville the Systems Support Equipment Laboratory designed the ground support equipment, a term applied to components used in the preparation, testing, monitoring, and launching of a rocket. The interface, or fit, of the launch vehicle and the support equipment largely determined the design of the latter. Accordingly, work in the Systems Support Equipment Laboratory paralleled Saturn development and was very much a research and design effort. Five design problems, in particular, challenged the laboratory: the launch pedestal, the hold-down and support mechanisms, the deflector, the cryogenic transfer equipment, and the umbilical tower.

Initial launch pedestal plans called for a hexagonal structure of tubular steel. George Walter, the laboratory's expert on structures, suggested a reinforced concrete design, which was eventually adopted. Walter's pedestal, 13 meters square and 8 meters high, was supported by corner columns and opened on all four sides to allow use of a two- or four-way flame deflector. A torus ring of large water nozzles, designed by Edwin Davis, encircled the 8-meter-wide exhaust opening. During launch and for some seconds thereafter, the nozzles would spray water on the pedestal, across the exhaust opening, and down the opening's walls, cooling the deflector and pedestal. 9

Atlas Missile Helium Bottle

A 1962 drawing showing the pad at LC-34, including the flame deflector, support arms, and hold-down arms.

The Pad Nightclub Bedford

The pad under construction, 1960.

Designing the eight vehicle support arms to be located on top of the pedestal proved a long and difficult task. Four of the arms, cantilevered at the Saturn's outboard engines, would retract horizontally after ignition, providing clearance for the engine shrouds at liftoff. Should one of the engines fail during the first three seconds following ignition, these four arms could return to the support position. The possibility of damaging the rocket as it settled back on its supports complicated the design of the arms. The Systems Support team developed a nitrogen-fed pneumatic device that brought the support arms safely back under the launch vehicle within 0.16 second. The remaining four support arms were designed to hold the vehicle on the pad for three seconds after ignition so that blockhouse instruments could test engine thrust. Donald Buchanan's design section considered more than 20 different proposals before selecting one suggested by Georg von Tiesenhausen, Deputy Chief of the Mechanical Branch. Von Tiesenhausen's concept, modeled after an old German bottle top, had been planned for use in securing a Jupiter seaborne model.* The hold-down arms employed an over-center toggle device to achieve the necessary leverage and rapid release capability. 10

The flame deflector design stirred debate within the laboratory: Should it have two or four sides? Should it be dry or wet (with cold water circulating through pipes beneath the metal shield)? The Huntsville engineers ruled out the four-sided deflector, previously used for Redstone and Jupiter missiles. The flame, spewing in all directions, would obstruct vision from the blockhouse and endanger equipment at the base of the umbilical tower. Both the size and cost of a wet deflector were unacceptable; one similar to those used on the test stands at Redstone Arsenal would cost ten times more than an uncooled deflector. Its size would increase the height of the launcher platform above ground, a dimension MFL wished to minimize. Despite doubts that a dry deflector could survive a single launch, a two-way uncooled deflector was selected. 11

Fueling the Saturn promised to be another problem. The booster required 182,200 liters of liquid oxygen (LOX), six times the amount expended by the Jupiter missile. The LOX would evaporate at a rate of 163 liters every minute during fueling and up until launch; some provision for replenishing this loss was required. Explosive hazards dictated placement of the LOX facility a minimum of 200 meters from the launch vehicle. Orvil Sparkman, a Huntsville native who had been working on propellants since 1953, was responsible for designing the cryogenics equipment.

The main storage tank would be an insulated sphere with a diameter of 12.5 meters; it could hold 473,125 liters of liquid oxygen. A centrifugal pump would deliver the LOX through an uninsulated aluminum pipe to the filling mast on the launcher. This was the "fast fill" and operated at 9,460 liters per minute. With some of the LOX boiling off as its temperature rose during the filling process, a smaller (49,205-liter) tank would send additional LOX through a vacuum-jacketed line to replace the boil-off, thus keeping the vehicle tanks full. Since the launch team wanted to automate LC-34 fueling, remote controls were designed for the launch control center. Early plans called for a differential pressure sensing system in the rocket's LOX and RP-1 tanks to control propellant flow (much as a washing machine controls flow by measuring the difference in pressure between the top and bottom of the tank). At Debus's request, the system was later replaced by an electrical capacitance gauge. The LOX tank's fuel level sensor also actuated a pneumatic valve on the replenishing line. 12

* In November 1955, Secretary of Defense Charles E. Wilson directed the Navy to adopt the Jupiter as a shipborne IRBM. Navy leaders, unenthusiastic about seagoing liquid-fueled rockets, subsequently were able to replace the Jupiter with the solid-propellant Polaris missile.

9. Davis interview; Walter interview, 21 Sept. 1973.

10. Von Tiesenhausen interview, 20 July 1973; Buchanan interview, 22 Sept. 1972.

11. Davis interview; Koelle, ed., Handbook of Astronautical Engineering, p. 28-44.

12. MSFC, C-1, C-2 Comparison, pp. 167-83; Wasileski interview, 14 Dec. 1972.

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